Why do some cars need people to hold/push it straight in the burnout box and others stay straight by themselves? I have run into this issue with my Crown Vic twice. The car is stock except the rear diff that has 3.55 gears and a trac-lok. The first time I was coming out of the car wash and attempted to shake all of the water, soap, and what not off of the rear tires. The car went immediately sideways. The second time was yesterday. I tested the limited slip a year ago by going to a parking lot and burning out in the snow (less than an inch). Both tires spin at the same time when examining the tire marks. So I figured everything is good. Just curious.